Ammonium dithiocarbamate

Ammonium dithiocarbamate has been prepared by using the following organic solvents as diluents for the reaction between carbon disulfide and anunonia esters alcohol ether and alcohol ketones ethers nitriles and nitro compounds. Isopropyl acetate is employed in the procedure that follows. 

throe-necked flask is fitted with a mechanical stirrer, a vent tube or reflux condenser, a thermometer, and an ammonia inlet tube.f Two liters of isopropyl acetate and 304 g. (4 mols) of carbon disulfide are added to the tared reaction flask. It is cooled to about 20° and ammonia is bubbled in with vigorous stirring. The rate of ammonia flow is carefully adjusted so that only a small excess passes out of the vent tube. A temperature of 20 to 30° is main- 

For the preparation of an aqueous solution of ammonium dithiocarbamate, 500 ml. of water is added to the reaction flask containing the slurry in isopropyl acetate. The mixture is agitated for a few minutes and the light yellow water solution of ammonium dithiocarbamate (lower layer) is separated from isopropyl acetate. The 3deld can be determined quite accurately by noting the increase in weight of the measured volume of water added. 

Dilute copper(II) sulfate solution gives a yellow floccu-lent precipitate when added to a dilute solution of anuno-nium dithiocarbamate. If a dilute solution of dithiocarbamate is heated to accelerate its decomposition, the resulting thiocyanate ion can be detected with iron (III) chloride. 

A good quantitative method for the determination of dithiocarbamate involves its precipitation as the sparingly soluble zinc salt. The precipitate is then dried at about 60 and weighed. An alternative procedure involves ignition to zinc oxide. Miller used a volumetric method 

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In 1891, Miolati (75) confirmed the cyclic formula of Liebermann and Lange by preparing the compound by three new pathways (1) reaction of CS2 on thiohydantoin, (2) condensation of ammonium dithiocarbamate with chloroacetic ester, (3) reaction of HjS on thiocyanoacetic acid. 

During a relatively long period, the condensation of rhodanines with aldehydes was developed, especially by Andreasch s group (78-87). Finally, Holmberg (88, 89) described the best method to obtain rhodanines the condensation of ammonium dithiocarbamate with a sodium or potassium salt of an a-chloro acid. 

In 1892, Marchesini (94) described the synthesis of 4-phenyl-2-mercaptothiazole (62) by condensing bromoacetophenone with ammonium dithiocarbamate. 

The results initially obtained were due to the formation in both aqueous and alcoholic solution of resinous by-products. This formation results from the decomposition of the ammonium dithiocarbamate, or from the self-condensation of chloroacetaldehyde or the formation of intermediate products. 

TABI.R n-25. 2-MERCAPTOTHIAZOLE DERIVATIVES FROM AMMONIUM DITHIOCARBAMATE AND o-HALOCARBONYL COMPOUNDS (163s)... 

Chloroacetone, phenacylbromide, a-bromoisobutyrophenone, 3-bromo-3-methyl-2-butanone, 1 -alkylsulfonyl-3-bromo-2-propanone, and ethyl-y-chloroacetoacetate give with ammonium dithiocarbamate the corresponding 4-hydroxythiazolidine-2-thiones (177), which have a characteristic absorption between 273 and 279 nm. Dehydration by heating with dilute HCl can be followed by ultraviolet spectroscopy because the products formed (175) absorb at 315 to 340 nm. 

Other sulfur compounds such as thiourea, ammonium dithiocarbamate, or hydrogen sulfide also lead to 2-mercaptothiazoles. Thus thiourea has been used in the syntheses of 4,5-dimethyl (369) and 4-aryl-2-mercapto-thiazoles (Table 11-30) (519). The reactions were carried out by condensing the ia -thiocyanatoketones with thiourea in alcohol and water acidified with hydrochloric acid. By this procedure, 4-aryl-2-mercaptothiazoles were obtained in yields of 40 to 80% with bis-(4-aryl-2-thiazolyl) sulfides as by-products (519). These latter products (194) have also been observed as a result of the action of thiourea on 2-chloro-4-arylthiazole under the same experimental conditions. They can be separated from 2-mercaptothiazoles because of their different degrees of solubility in sodium hydroxide solution at 5%. In this medium bis-(4-phenyl-2-thiazolyl)sulfide is... 

Manufacture. An extensive technology was developed initially ia the 1930s for isolation of ammonium thiocyanate from coke-oven gases, but this technology is no longer practiced ia the United States (372). However, such thiocyanate recovery processes are used iadustrially ia Europe. Likewise, the direct sulfurization of cyanides to thiocyanates is not practiced commercially ia the United States. The principal route used ia the United States is the reaction of carbon disulfide with aqueous ammonia, which proceeds by way of ammonium dithiocarbamate [513-74-6]. Upon heatiag, the ammonium dithiocarbamate decomposes to ammonium thiocyanate and hydrogen sulfide. 

At approximately 160°C, some of the ammonium thiocyanate is converted to thiourea [62-56-6] H2NCSNH2, iulow yield. With alcohoHc ammonia, ammonium dithiocarbamate [513-74-6] forms ... 

The major difference in the dithiocarhamato chemistry of tantalum and niobium is the existence of the Ta(V) species Ta(R2C tc)5, whereas the comparable niobium compound is unknown. The preparative methods for Ta(R2C tc)5 involve either a CS2 insertion in Ta(NR2)j (R = Me )) or a reaction between TaClj and sodium or ammonium dithiocarbamate (R = Et (7), R2 = ( 112)4 ( ))- The structure of this interesting diamagnetic compound is not elucidated, but from infrared data the presence of one or more unidentate ligands is suggested 11,15). 

Craig and co-workers247 reported the synthesis of l-aza-2,4,10-trithiaada-mantane (227) as a by-product in the reaction of ammonium dithiocarbamate with an aqueous solution of chloroacetaldehyde. The same compound is reported to be obtained by the reaction of mercaptoacetaldehyde with ammonia248 and then by the reaction of tri(2,2-bis(ethoxy)ethyl]amine (228) with hydrogen sulfide in the presence of hydrobromic acid.249 The... 

Organic compounds having four alkyl groups attached to nitrogen. A quaternary ammonium salt is employed in reversing the electric charge on natural rubber latex quaternary ammonium dithiocarbamates are ultra-accelerators for rubber vulcanisation. 

Statham [448] has optimised a procedure based on chelation with ammonium dithiocarbamate and diethylammonium diethyldithiocarbamate for the preconcentration and separation of dissolved manganese from seawater prior to determination by graphite furnace atomic absorption spectrometry. Freon TF was chosen as solvent because it appears to be much less toxic than other commonly used chlorinated solvents, it is virtually odourless, has a very low solubility in seawater, gives a rapid and complete phase separation, and is readily purified. The concentrations of analyte in the back-extracts are determined by graphite furnace atomic absorption spectrometry. This procedure concentrates the trace metals in the seawater by a factor of 67.3. 

Ammonium dithiocarbamate, 4 826 Ammonium dithiocyanatoaurate(I), 7 596 Ammonium fluoride, 2 714 Ammonium fluoroborate manufacture, 4 155 physical properties of, 4 152t thermodynamic properties of, 4 154t uses of, 4 156-157 Ammonium fluorohafnate, 13 91-92 Ammonium glycyrrhizinate, 12 49 ... 

Forms ammonium carbamate, NH2 COO NH4 with CO2 and ammonium dithiocarbamate, NH2 CSS NH4 with CS2 ... 

Ammonium thiocyanate is made in the United States by the reaction of carbon disulfide with aqueous ammonia. Ammonium dithiocarbamate is formed as an intermediate in this reaction, which upon heating, decomposes to ammonium thiocyanate and hydrogen sulfide. 

Pt(S2CNMe(Hex))2] and [Pd(S2CNMe(Hex))2] have been synthesized and used as precursors to grow the first TOPO-capped PtS and PdS nanoparticles and thin films of PtS and PdS by the metallo-organic chemical vapor deposition (MOCVD) method [204]. Platinum and palladium chalcogenides find applications in catalysis [205-210] and materials science [211,212]. The synthesis of thiocarbamato complexes of platinum and palladium from reaction of an aqueous solution of ammonium dithiocarbamate with the platinum or palladium salt has been reported by Nakamoto et al. [213]. However... 

Isothiocyanates can be prepared from support-bound primary amines by treatment with thiophosgene [14] or synthetic analogs thereof (Entry 5, Table 14.2). In an alternative two-step procedure, the amine is first treated with CS2 and a tertiary amine to yield an ammonium dithiocarbamate, which is subsequently desulfurized with TsCl or a chloroformate (Entry 6, Table 14.2 Experimental Procedure 14.1). Highly reactive acyl isothiocyanates have been prepared from support-bound acyl chlorides and tetra-butylammonium thiocyanate (Entry 7, Table 14.2). These acyl isothiocyanates react with amines to give the corresponding 7V-acylthiourcas, which can be used to prepare guanidines on insoluble supports (Entry 6, Table 14.3). 

Ammonium dithiocarbamates can be prepared through reaction (11). With HC1 or H2S04 at lower temperatures the free acids are formed. Only one transition metal complex (37) is known, with a pseudo-octahedral coordination of Ni four sulfur atoms of the dithiocarbamate in the equatorial plane and two pyridine solvent molecules at the apical positions. Sulfides can be eliminated from monosubstituted dithiocarbamates to give isothiocyanates.53... 

Unsubstituted and mono substituted ammonium dithiocarbamates react with sodium chloro-acetate to produce different rhodanines, from which numerous metal complexes have been made.55... 

Reactions of alkynyliodonium salts with multidentate nucleophiles can be employed for the synthesis of heterocyclic compounds. Recent examples include preparations of thiazoles, selenazoles, and 2-mercaptothiazoles by the treatment of alkynyliodonium mesylates or tosylates with thioamides, selenoamides, and ammonium dithiocarbamate (Scheme 62) [169-171]. A novel hetero-Claisen rearrangement of tricovalent iodine(III) intermediates was proposed to account for the 2,4-disubstitution pattern of the thiazoles [169]. 

For these reasons, in the present work, the reaction of 3-(2-bromoacetyl)-4-hydroxychromen-2-one (18) with thioureas, thioacetamides and ammonium dithiocarbamate have been investigated. Compound 18 was synthesized from 3-acetyl-4-hydroxychromen-2-one (17) and used as a suitable synthone for further reactions. The 4-hydroxycoumarin nucleus is very susceptible to... 

Finally, compound 18 was also reacted with ammonium dithiocarbamate to give 4-hydroxy-3-(2-mercaptothiazol-4-yl)chromen-2-one (21) (Scheme 9). 

Scheme 9 Reaction of compound 18 with ammonium dithiocarbamate...

Furthermore, eight 3-(thiazol-4-yl)-4-hydroxychromen-2-one derivatives were prepared in good yields in the reaction of 3-(2-bromoacetyl)-4-hydroxychromen-2-one with thioureas, thioacetamide, thiobenzamide and ammonium dithiocarbamate. The obtained coumarin derivatives can be used as potentially bioactive compounds and as precursors in the synthesis of medications. 

Two approaches to the mercaptothiazoles 31 by the HTIB-method have been described one in which the a-TK are initially converted to a-thiocyanato ketones, and a more direct route involving treatment of the a-TK with ammonium dithiocarbamate (Scheme 8) (93SC1455, 01SC415). The mercaptoimidazoles 32 can be prepared by a one-pot sequence in which a-amlino ketones are generated from a-TK intermediates and cyclized with potassium thiocyanate (Scheme 8) (94IJC(B)116). 

A. Ammonium dithiocarbamate. Gaseous ammonia is passed into 2S0 ml. of 95% ethanol (Note 1) contained in a 1-1. Erlen-meyer flask immersed in an ice bath until the gain in weight is 39 g. (2.3 moles). To this solution, still cooled by the ice bath, is added a well-cooled mixture of 76 g. (60 ml., 1 mole) of carbon... 

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